1. Field of the Invention
The present invention relates in general to the field of utility meters. More particularly, the present invention relates to automatic equipment, systems, networks, and software for remote reading of utility meters, such as electric, gas, water, or steam meters.
2. Description of Related Art
Utility companies and municipalities for many years have been burdened with the labor intensive and cumbersome task of manually collecting meter readings, managing data from the field into the accounting area, and managing the billing and collection of invoices. Typically each customer is provided with a mechanical utility meter for each individual service provided, for example, a meter for water, a meter for steam, a meter for gas, and a meter for electric power. A periodic reading of the utility meter is necessary to determine the usage and to bill the customer for the amount used. These meters are normally manually read using utility company or municipality employees physically visiting each meter at the customer's location, reading the meter, and recording the previous month's usage into a written route book for delivery to accounting personnel. This process is costly, is time consuming, and can involve various risks to personnel involved in manually collecting meter data. The process involves labor, motorized transportation, and numerous employee overhead-related costs. Once the readings from the meter are obtained, accounting personnel manually transfer the readings into a database for billing and collection of the invoices for service.
Manually reading the meters often results in numerous other expenses including those related to human error. For example, a high bill caused by an incorrect manual read or estimated read often motivates customers to pay later, resulting in increased working capital requirements and corresponding expenses for the utility. Additionally, the utility has to handle the customer complaints (a call center cost) and may have to read the meter again to verify the error. As the complaint progresses, the utility faces administrative costs associated with routing and processing the complaint from the call center to the meter department. An additional cost includes the potential loss of a customer who, even after resolution, feels the process was such an excessive burden as to prompt the customer to switch utility providers.
Recently, hand-held reading units have been developed that typically provide a data collection unit attached to the consumer's utility meter having some form of data transmitter. The unit or system has some form of receiver. There are different variations in methodology of receiving the data. One methodology of hand-held “local” collecting meter reading requires an operator having a meter or collection unit interrogation device to be in close physical proximity of the meter to obtain the meter reading and transport the data to a central computer such as shown in U.S. Pat. No. 5,559,894 by Lubliner et al. titled “Automated Meter Inspection and Reading” and U.S. Pat. No. 5,856,791 by Gray et al. titled “Port Expander For Utility Meter Reading.” For example, in a radio drive-by or walk-by unit, a utility service vehicle having a mobile receiver mounted in a service vehicle or a utility worker having a hand-held unit passes by the consumer's facility to receive the data from the meter. As the vehicle or hand-held unit passes near the electric meter, the receiver emits a signal to the collection unit, which causes the collection unit to transmit or send its meter reading data to the receiver. This consumption data is then stored and later entered into a billing system. This approach, however, still requires the manual visit to each meter location and time downloading the data to the billing system. Nevertheless, the physical meters can be read much more quickly which reduces manpower, vehicular, and soft costs. Also, the data is transferred from the mobile receiver to the database, which again reduces manpower and data handling. This methodology also has a benefit to the customer of preventing intrusion into the customer's premises and improved accuracy of the reading. Remaining system negatives, however, included prohibitive capital costs, i.e., vehicles, and software and hardware requirements, and providing a reliable and cost-effective power solution for the individual radio transmitter in the individual meters.
Recently, automatic meter reading (“AMR”) has been developed. Automated meter reading has become more desirable than using meters that require manual reading and recording of the consumption levels. AMR consists of technologies and methods to remotely read a plurality of electric meters, such as a consumer base for an electric power supply company, into a billing database by installing or utilizing fixed networks that allow billing or meter usage data to be transmitted without human intervention to a host computer having the billing database. AMR produces many benefits and several companies such as Hunt Technologies, Schlumberger, CellNet, Itron, Amco Automated Systems, and Distribution Control Systems have developed AMR units. For the utility, reading meters without setting foot on customer's property substantially reduces risks associated with climbing over fences, slipping on ice and snow, dangerous animals, snakes, and spiders, and other types of risks which in turn, result in significant savings in liability insurance, disability benefits, and worker turnover/replacement. For the customer, reading meters without entering a customer's property provides a less intrusive service and reduces criminal activity such as when a criminal manages to gain entry into a customers property by posing as a meter reader. Moreover, the need for a higher frequency of meter reading is increasing, e.g., daily, hourly, or every 15 minutes, in order to take advantage of real time pricing. Also, the amount of data is increasing, due to the necessity to bill on more than just consumption, e.g., time of use. Thus, automated recording and reporting of the utility usage at customer sites is rapidly replacing the manually read utility meters.
AMR systems can use a dial-up modem in the collection unit to dial a remote billing system and transmit its reading data via telephone lines such as that shown in U.S. Pat. No. 6,163,602 by Hammond et al. titled “System and Method for Unified Telephone and Utility Consumption Metering, Reading, and Processing” and U.S. Pat. No. 5,128,988 by Cowell et al. titled “Telephone Switched Network, Automatic Meter-Reading System Based Upon Service Address.” In the past, there have been on-site meter reading equipment having a modem capable of receiving telephone calls from a central office through the use of special equipment located at the telephone company, and there have also been on-site meters with modems which were capable of placing telephone calls to the central office. In general, these systems incorporate an auto-dial, auto-answer modem in each customer site to receive interrogation signals from the telephone line and to formulate and transmit meter readings via the telephone line to the utility company. These systems record information on utility usage and periodically dial into a central office to report the utility usage for recording and billing purposes. This methodology provides two-way communication and control between the meter and the central office. The modem shares the telephone line with the customer's normal usage, such as incoming and outgoing voice communications. Such sharing requires that the system be able to recognize when the telephone line is in use, and to delay demanding use of the telephone line until it is free. Steps must be taken to prevent the data communications system from interfering with other uses and to prevent other uses from corrupting the transmitted data.
A variation of this methodology includes using the power line as a carrier medium. This approach connects the meter through the power lines and relays the meter reading over the power lines to the utility company. This approach, however, can require a complicated infrastructure to be installed. Power lines operate as very large antennas and can receive a large amount of noise. Therefore, signal-cleaning filters must be installed periodically along the power lines to attenuate the noise. These filters can be very expensive. Also, the connections often are at line voltage, making it more dangerous and time consuming to install.
Another problem with expanding the use of control systems technology to such distributed systems are the costs associated with the sensor-actuator infrastructure required to monitor and control functions within such systems. A more modem approach to implementing control system technology is to install a local network of hard-wired sensors and actuators along with a local controller. Not only is there the expense associated with developing and installing appropriate sensors and actuators, but there is the added expense of connecting functional sensors and controllers with the local controller and the cost of the local controller. This methodology is also quite intrusive as the cables must be run to physically interconnect the various nodes in the network. An alternative variation includes interfacing the meter with a community cable television system. In addition to the high cost of installation, however, such a system is not useable in areas without access to a cable system. Moreover, networks that are interconnected with cables are subject to physical disruption of the cables.
Recently, wireless networks have been developed. These networks, typically installed in a point-to-point loop configuration, are used to collect information from and to disseminate information to individual nodes of the network. In conventional wireless networks using a point-to-point loop configuration, each node in the network is interconnected and communicates with two neighboring nodes. Information or commands are passed from node to node around the point-to-point loop until they arrive at a master node. The master node is used to communicate information that is gathered to a central station or to accept and distribute information received from a central station throughout the network. These conventional wireless networks, however, have limitations. For example, because these conventional wireless networks generally have a point-to-point loop configuration, when one node is disabled, the integrity of the entire network can be affected. Moreover, if the master node of such a conventional network is disabled, the network can become isolated.
Other variations in methodology include using data channels in wireless telephone systems to transmit usage data to a remote billing system via a wireless telephone network, such as PCS, satellite, or cellular. Other methodologies also include the use of low earth orbiting satellites. Building, launching and maintaining a fleet of satellites, however, is very expensive.
Yet another methodology includes the use of small RF transmitters. Because systems having sufficient range normally are subject to regulations and licensing requirements that are prohibitively expensive, however, the centralized wireless control systems for locally distributed devices using RF transmitters have not been widely utilized. Also, systems that are sufficiently powerful to be used in widely distributed installations are unnecessarily expensive in smaller installations. Additionally, there is limited availability of RF carrier frequencies, and potential interference with other nearby systems that might be operational.
Further AMR servers have been developed, such as shown in U.S. Pat. No. 6,088,659 by Kelley et al. titled “Automated Meter Reading System,” in attempts to address the metering data management needs of entities involved in energy distribution. Such AMR servers use an open, distributed architecture that collects, loads, and manages system-wide data collected from energy meters and routes data automatically to upstream business systems. Although such AMR servers may address some meter data management concerns, these systems still fail to address communication concerns set forth above with respect to collecting billing or usage data and transmitting the data to a control center, e.g., perhaps having an AMR server.